Last week we were taking great strides towards completing the 944. The motor and clutch were installed with the new and improved flywheel/coupler. The batteries were installed and wired up. All of the accessories were mounted and wired as well. We had our first trial run using the full battery voltage and the controller. After a slight polarity issue from the key-switch, we had ignition (contact closure actually). With the drive wheels lifted off the ground, we spun up the motor - and had some seriously noisy shaking!

With our latest flywheel design, there was no way we should be getting vibrations like this. What seemed harmless at 12V was disasterous at 180V. So we had to remove the entire system to do root cause analysis.

To make a long story short - the clutch pressure plate had a broken spring! Our flywheel was spinning nice and true, as was the clutch/pressure plate. But, once the drive shaft was insterted into the system, the pressure plate's broken spring was unloading 1/3 of the clutch disc and essentially twisting the disc, transmitting a lot of movement into drive shaft/transmission and the rest of the car. At least it wasn't our flywheel design.

So yesterday I picked up a good-used pressure plate from Nineapart.com so we should be up and running again in no time.

While the batteries are back sitting in my living room again, it may be a good opportunity to take care of waterproofing the battery racks in case we get stuck driving through the rain at some point. We made a few structural modifications to the car during the last disassembly of the system so that we can now assemble the battery packs outside of the car and use the crane to drop in the whole pack all at once. This should save a lot of time if we ever have to remove the batteries again.